Isye 6501 midterm 2 - Course. ISYE 6501. Institution. ISYE 6501. ISYE 6501 Midterm EXAM QUESTIONS AND SOLUTIONS LATEST UPDATE 2023/2024 Factor Based Models classification, clustering, regression. Implicitly assumed that we have a lot of factors in the final model Why limit number of factors in a model? 2 reasons overfitting: when # of factors is close ...

 
Study with Quizlet and memorize flashcards containing terms like Time between people entering the ID-check queue at an airport -exponential -binomial -geometric -weibull -poisson, Number of penalty kicks taken at the World Cup until one of them is saved by the goalkeeper -Poisson -Exponential -Weibull -Binomial -Geometric, Number of eggs inspected until the first cracked one is found -Weibull .... Green oval pill 44375

Lecture Notes ISYE 6501 Midterm 1. Analytic models 100% (25) 8. Lessons 17-21 Notes ISYE 6501. Analytic models 100% (6) 4. ISYE 6501 Homework 3 Submission (R) Analytic models 100% (4) 1. ISYE 6501- Solution 6-1. Analytic models 100% (4) More from: Analytic models ISYE 6501. Georgia Institute of Technology.ISYE 6501 Midterm 2.pdf. Solutions Available. Georgia Institute Of Technology. CS ISYE6501X. GT Students and Verified _ Midterm Quiz 1 _ ISYE6501x Courseware _ edX.pdf. Solutions Available. Georgia Institute Of Technology. ISYE 6501. Trending in ISYE 6501. Final Exam.pdf. Solutions Available.Developed by Microsoft and included in its Office suite of productivity software, Word allows you to create print-formatted documents such as letters, envelopes, brochures and form...Okay since everybody is so curious to know, for ISYE6501. At the end of each test, once the results are tabulated, factoring the difficulty, Prof Joel Sokol will publish an indicative cut-off for that test (and only for that test). That is to say, of all things remaining the same, that would be your final grade.101F20 Midterm 2 answers.pdf. Drexel University. MATH 102. 2180 Midterm Answers Spring 2021.pdf. George Washington University. ECON 2180. Midterm 1 S2021 Answers.pdf. ... View ISYE6501 Final with Answers SP21.pdf from ISYE 6501 at Georgia Institute Of Techno... BPS2110 Midterm1 2015 Answers.pdf. University of Ottawa. BPS …ISYE 6501 Midterm 2/ ISYE 6501 O01 OAN O01 MS Updated 2023... - $15.45 Add to Cart Browse Study Resource | Subjects Accounting Anthropology Architecture Art Astronomy Biology Business Chemistry Communications Computer Science Question 14 2 / 2 pts. Answer 1: Answer 2: i. The simulation [ Select ] have been stopped after 400 runs (replications). ii. The simulation [ Select ] even have been stopped after 300 runs (replications). ct!ct! COULD. ct!ct! COULD. Question 15 0 / 1 pts. Answer 1: The simulated wait time WAS NOT 50 or less at least once out of all the runs ... E [Y] = r/p; Var (Y) =qr/p 2. Counting Process, N (t): keeps track of number of arrivals observed between time 0 and timet. Disjoint time increments are independent (Arrivals in one interval don’t impact arrivals in another). Increments are stationary (Distribution doesn’t de- pend on start time of interval).Behind his jokes, every video curated by Prof Sokol are important. These are where the midterm/final exam questions are out. It was only prior to Midterm 2 when I made sure every single video is watched, reviewed, re-watched 1.25x and 1.5x to ensure every single piece of information is understood.View Midterm_2.pdf from ISYE 6501 at Georgia Institute Of Technology. Midterm 2 Prep Monday, November 2, 2020 7:12 AM By: Chris Dedow • 11.2 Models for Variable Selection Good for initial analysis,Miles_Porter2. Study with Quizlet and memorize flashcards containing terms like Overfitting, Fitting random effects, Simple Models and more.ISYE 6501 Midterm 2 Intro Analytics Modeling - ISYE-6501-OAN O01 QCH ASY. exam 2. Course. Intro to Analytics Modeling (ISYE 6501) 815Documents. Students shared 815 …what is backward elimination. we start with all factors and find the worst on a supplied threshold (p = 0.15). If it is worse we remove it and start the process over. We do that until we have the number of factors that we want and then we move the factors lower than a second threshold (p = .05) and fit the model with all set of factors.1) start with all the factors 2) find worst current factor 3) is it bad enough (high enough p value typically above .15)? yes - remove it go back to step 2 no - go to step 4 4) do we have too many factors yes - remove it go back to step 2 no - go to step 5 5) remove factors with high p value (typically p value above .05) 6) fit model with final ...Prof Jokol will provide the curves for each midterms. r/OMSA users are usually people who score better. Iirc the ta's will post the grade distribution in more detail than the standard mean/max/min values that canvas provides. They additionally provide pseudo guidance on how the test would be curved it it was curved.ISYE 6501 Homework solution for week #1 question describe situation or problem from your job, everyday life, current events, etc., for which classification ... Lecture Notes ISYE 6501 Midterm 1. Analytic models 100% (25) 8. Lessons 17-21 Notes ISYE 6501. Analytic models 100% (6) 4. ISYE 6501 Homework 3 Submission (R) Analytic models 100% (4) 1.ISYE 6501 - Midterm 2 Terms in this set (160) when might overfitting occur when the # of factors is close to or larger than the # of data points causing the model to potentially fit too closely to random effects Why are simple models better... By bundleHub Solution guider , Uploaded: Jul 13, 2022. $10.The veteran Senator from Texas, Ted Cruz, faces a stiff challenge from up and coming Beto O’Rourke in the 2018 Midterm elections. Recent polls show Cruz’s lead shrinking to as litt... The less fit the model is the fewer variables we use and the smaller the coefficients get every prediction by the model gets closer to constant term a0 regardless of the value of x removing variables and shrinking coefficients creates bias in the model - model misses/minimizes real patterns in the data underfitting real effects while eliminating variance from random effects The questions will be similar to the first midterm. The tips for preparation would be review all the lecture materials. When I took the course, there was a lot of good student feedback on Piazza. When you have specific questions about a course in progress that you are in, Piazza is the best place to ask questions. 3.As the midterm elections inch closer, political action committees (PACs) are beginning to focus on funding candidates that align with their objectives. Crypto-backed Super PACs are...ISYE 6501 Midterm 2.pdf. Solutions Available. Georgia Institute Of Technology. CS ISYE6501X. GT Students and Verified _ Midterm Quiz 1 _ ISYE6501x Courseware _ edX.pdf. Solutions Available. Georgia Institute Of Technology. ISYE 6501. Trending in ISYE 6501. Final Exam.pdf. Solutions Available.Representatives to the U.S. House of Representatives are elected every two years. This means that all representative seats are up for election at the same time, both in the years o...HW W2 - Homework for week 2; ISYE 6501 HW6 HTML; Homework 5 ISYE 6501; Course Project; HW 9 - homework number 9; HW 8 - homework number 8; Related documents. HW 10 - homework number 10; ... Midterm 1 cheatsheet for exam prep, can be use on exam. Intro to Analytics Modeling 92% (13) 21. Homework 4 ISYE 6501. Intro to Analytics …Midterm 1 – Solutions ISyE 6501, Fall 2022. September 13, 2022. Question. [True or False; Give brief justification] Classification is a pervasive problem that encom- passes many diverse applications.erpret what is forward selection we select the best new factor and see if it's good enough (R^2, AIC, or p-value) add it to our model and fit the model with the current set of factors. Then at the end we remove factors that are lower than a certain threshold what is backward elimination we start with all factors and find the worst on a supplied threshold (p 0.15). If it is worse we remove it ...ISYE 6501 Midterm 1 (FA22) Score for this quiz: 75 out of 100 95 Minute Time Limit Instructions Work alone. Do not collaborate with or copy from anyone else. You may use any of the following resources: One sheet (both sides) of handwritten (not photocopied, scanned, or printed) notes If any question seems ambiguous, use the most …ISYE 6501 Midterm 2 Intro Analytics Modeling - ISYE-6501-OAN O01 QCH ASY. exam 2. Course. Intro to Analytics Modeling (ISYE 6501) 815Documents. Students shared 815 …In modeling, it’s essential to understand how to choose the right data sets, algorithms, techniques, and formats to solve a particular business problem. In this course, you’ll gain an intuitive understanding of fundamental models and methods of analytics and practice how to implement them using common industry tools like R.A. The 14th person's family size and car type B. The 14th person's family size C.The car type of each person - CORRECT ANSWERS A. A data point is all the information about one observation The farther the wrongly classified point is from the line ___ - CORRECT ANSWERS The bigger the mistake we've made The term including the margin gets larger so ...ISYE_6501 Activity. Stars. 4 stars Watchers. 1 watching Forks. 21 forks Report repository Releases No releases published. Packages 0. No packages published . Languages.Study with Quizlet and memorize flashcards containing terms like Time between people entering the ID-check queue at an airport -exponential -binomial -geometric -weibull -poisson, Number of penalty kicks taken at the World Cup until one of them is saved by the goalkeeper -Poisson -Exponential -Weibull -Binomial -Geometric, Number of eggs …erpret what is forward selection we select the best new factor and see if it's good enough (R^2, AIC, or p-value) add it to our model and fit the model with the current set of factors. Then at the end we remove factors that are lower than a certain threshold what is backward elimination we start with all factors and find the worst on a supplied threshold (p 0.15). If it is worse we remove it ...Truck driver duties encompass a wide range of responsibilities. By crafting accurate and engaging descriptions for truck driver jobs, employers can attract qualified candidates. Tr...Institution. ISYE 6501. ISYE 6501 - Midterm 2 Exam 2024 when might overfitting occur - answerwhen the # of factors is close to or larger than the # of data points causing the model to potentially fit too closely to random effects Why are simple models better than complex ones - answerless data is required; less chanc... [Show more]Midterm Quiz 2 - GT Students and Veri±ed MM Learners Midterm Quiz 2 due Nov 8, 2020 23:00 PST Completed 90 Minute Time Limit Instructions Work alone. Do not collaborate with or copy from anyone else.ISYE 6501, Introduction to Analytics Modeling. Midterm #2 – Friday, November 8, 2019. 50 minute time limit. INSTRUCTIONS • Work alone. Do not collaborate with or copy from anyone else. • Write all of your answers on the answer sheet. • You may use any of the following resources:Quiz History- ISy E 6501 Final Quiz copy; ISYE 6501 Midterm 2 - practice material; ISYE6501 Homework 4 - eee; Super cheatsheet machine learning; Final Cheat 1; Related Studylists 6501 Final Exam Prep ISYE 6501 FINAL final. Preview text. ISyE 6501 Final Quiz Due May 2 at 2am Points 100 Questions 63ISYE 6501 gives a high-level overview of data preparation, modeling, and other analytical techniques (such as simulation). It's a great introduction to the OMS Analytics program. The course consists of: 3 exams (2 midterms and 1 final) each worth 25%, homework worth a collective 16%, and a final project worth 9%.ISYE 6501/ISYE6501 MIDTERM EXAM 49 QUESTIONS WITH 100% COMPLETE SOLUTIONS/A+GRADE GUARANTEED/2023|A GRADED INSTRUCTIONS FOR QUESTIONS 1-5 For each of the following five questions, select the probability distribution that could best be used to model the described scenario.R 68.5%. HTML 23.6%. Python 7.9%. ISYE_6501. Contribute to madhan1m/ISYE6501 development by creating an account on GitHub.NAME_____ ISYE 6501, Introduction to Analytics Modeling Midterm #1 – Wednesday, October 5, 2022 75 minute time limit INSTRUCTIONSMar 19, 2023 · A. The 14th person's family size and car type B. The 14th person's family size C.The car type of each person - CORRECT ANSWERS A. A data point is all the information about one observation The farther the wrongly classified point is from the line ___ - CORRECT ANSWERS The bigger the mistake we've made The term including the margin gets larger so ... ISYE 6501 Midterm 1 _ Intro Analytics Modeling - ISYE-6501_O01-OAN_O01_MSA.pdf Move To This element is a more accessible alternative to drag drop reordering from ISYE... ISYE 6501 Midterm 2.pdfThere is no controversy: The 14th amendment says what it says. Donald Trump said earlier this week he intends to end birthright citizenship through an executive order, part of his ...Midterm elections in the U.S. don't get the public excited the way presidential elections do. But there's a lot at stake, actually, during these contests. Why do midterms exist, an...The less fit the model is the fewer variables we use and the smaller the coefficients get every prediction by the model gets closer to constant term a0 regardless of the value of x removing variables and shrinking coefficients creates bias in the model - model misses/minimizes real patterns in the data underfitting real effects while eliminating …ISYE 6501 Midterm 2 Due Jul 12 at 2am Points 100 Questions 48 Available after Jul 1 at 2am Time Limit 90 Minutes Instructions onorlock Chrome Extension s exam requires Google Chrome and the Honorlock Chrome Extension. ... ISYE 6501 Midterm 2. Due Jul 12 at 9amPoints 100.02. Questions 48. A vailable after Jul 1 at 9am. Time Limit 90 Minutes. Instructions. . Honorlock Chrome. Extension. Related documents. CSE 6040 x - Fall 2021 - Schedule; 8_sol; Course Project; ISYE 6501 Final Project; Assingment 4 HW - Home work for 2022; Isye 6501 syllabus and schedule 2022-2ISYE 6501 Midterm Quiz 1 - GT Students Launch Proctortrack first before taking the Midterm Quiz 1 4. GTx: ISYE6501x Introduction to Analytics Modeling Midterm Quiz 2ISYE 6501 Midterm 2 Part 1 QUESTIONS WITH COMPLETE SOLUTIONS. greedy algorithm correct answer: at each step, the algorithm does the thing that looks best without taking future options into consideration; more classical variable selection methods correct answer: stepwise - (forward, backward, combination) lasso elastic net available …View Midterm_2.pdf from ISYE 6501 at Georgia Institute Of Technology. Midterm 2 Prep Monday, November 2, 2020 7:12 AM By: Chris Dedow • 11.2 Models for Variable Selection Good for initial analysis, 2) Use categorical variables to indicate missing data. 3) Estimate missing values (imputation) Different ways of estimating missing data (2) 1) Mid-range value (mean, median, mode) 2) Use a predictive model (like regression) Adding a random value (up or down) to model-predicted imputed data. Perturbation. ISYE 6501 Midterm Quiz 1 - GT Students Launch Proctortrack first before taking the Midterm Quiz 1 4. GTx: ISYE6501x Introduction to Analytics Modeling Midterm Quiz 2ISYE 6501. Institution. Georgia Institute Of Technology. ISYE-6501-OAN/O01 -- HOMEWORK 9 – SOLUTIONS 12.1 As a software engineer of a service-oriented company, we try to upsell many products to the customers and want to display the ads of a product/service within the mobile application. Most of the time we don’t have much idea about the ...ISYE 6501 Bundle with final Solution(A+ docs piled) Last document update: ago ISYE 6501 Midterm Quiz 1 with all the Correct Answers(Graded A+) ISYE 6501 Midterm Quiz 2 - GT Students and Verified MM Learners GT Students and Verified _ Midterm Quiz 1 with complete solution Latest 2021 ISYE 6501 Final …Packages. No packages published. Masters Data Science. Contribute to eastoj/Georgia-Tech development by creating an account on GitHub.Packages. No packages published. Masters Data Science. Contribute to eastoj/Georgia-Tech development by creating an account on GitHub.Midterm 1 – Solutions ISyE 6501, Fall 2022. September 13, 2022. Question. [True or False; Give brief justification] Classification is a pervasive problem that encom- passes many diverse applications.The 2022 midterm elections are quickly approaching. Here are the stocks that investors should be watching carefully as a result. Stocks have a history of being volatile around midt...ISYE 6501 Midterm 2 Intro Analytics Modeling - ISYE-6501-OAN O01 QCH ASY. Intro to Analytics Modeling 100% (5) 45. ISYE 6501 Midterm 2 - practice material. Intro to Analytics Modeling 100% (3) 12. ISYE6501 Homework 4 - eee. Intro to Analytics Modeling 100% (2) 67. Quiz History- ISy E 6501 Final Quiz copy.ISYE 6501. Subject. Computer Science. Date. Jul 17, 2023. Pages. 38. Uploaded by AgentSeahorseMaster1773 on coursehero.com. Helpful. Unhelpful. Home / …Midterm 1 – Solutions ISyE 6501, Fall 2022. September 13, 2022. Question. [True or False; Give brief justification] Classification is a pervasive problem that encom- passes many diverse applications.ISYE 6501 Midterm 2 - practice material. practice material. Course. Intro to Analytics Modeling (ISYE 6501) 845Documents. Students shared 845 documents in this course. University. Georgia Institute of Technology. Academic year:2022/2023. Uploaded by: Anonymous Student.BUNDLED PAPERS (Multiple versions) FOR Georgia Institute Of Technology ISYE 6501 Homeworks 1 - 15, Midterm 1 & 2 FINAL EXAM | ISYE6501x Courseware | edX - Complete Solutions - Introduction To Analytics Modeling - GTX ISYE 6501ISyE 6501 Final Quiz Due May 5 at 2am Points 100.04 Ques!ons 63 Available un!l May 5 at 2am Time Limit 180. AI Homework Help. Expert Help. Study Resources. ... ISYE 6501 Midterm 2 : Intro Analytics Modeling - ISYE-6501:O01-OAN:O01:MSA.pdf. Solutions Available. Georgia Institute Of Technology. ISYE 6501. Week 7 tests.docx.I got a 91. All of my study time was spent rewatching the lecture videos taking detailed notes and creating my cheetsheet. The only outside sources I used was to better understand PCA, because frankly it confuses the hell out of me. When taking the exam I didn’t spend too much time rereading the questions.ISYE 6501, Introduction to Analytics Modeling. Midterm #2 – Friday, November 8, 2019. 50 minute time limit. INSTRUCTIONS • Work alone. Do not collaborate with or copy from anyone else. • Write all of your answers on the answer sheet. • You may use any of the following resources:View midterm-2-cheatsheet-from-the-lectures.pdf from ISYE 6501 at Georgia Institute Of Technology. lOMoARcPSD|22219125 Midterm 2 cheatsheet from the lectures Analytic models (Georgia Institute of. AI …Will learning a language help me professionally? Visit HowStuffWorks to find out if learning a language will help you professionally. Advertisement Looking for a job is a full-time...Related documents. CSE 6040 x - Fall 2021 - Schedule; 8_sol; Course Project; ISYE 6501 Final Project; Assingment 4 HW - Home work for 2022; Isye 6501 syllabus and schedule 2022-2ISYE 6501 Midterm 2.pdf. Solutions Available. Georgia Institute Of Technology. CS ISYE6501X. Trending in ISYE 6501. Final Exam.pdf. Solutions Available. Georgia Institute Of Technology. ISYE 6501. ISYE6501 Final with Answers SP21.pdf. Georgia Institute Of Technology. ISYE 6501. CITIC_notes.docx.View ISYE_6501_Midterm_2___solution - 5.pdf from ISYE 6501 at Georgia Institute Of Technology. 5/1/2020 Midterm Quiz 2 - GT Students and Verified MM Learners | Midterm Quiz 2 | ISYE6501x Courseware |Other - Isye 6501 lecture notes midterm 2 4. Exam (elaborations) - Gt students and verified midterm quiz 1 5. Exam (elaborations) - Isye 6501 final quiz summer 2018 ...Mar 19, 2023 · A. The 14th person's family size and car type B. The 14th person's family size C.The car type of each person - CORRECT ANSWERS A. A data point is all the information about one observation The farther the wrongly classified point is from the line ___ - CORRECT ANSWERS The bigger the mistake we've made The term including the margin gets larger so ... ISYE notes before midter 1. OMSA ISYE6501Syllabus-combined-Fall 2022. ISYE 6501Timeline 1-15. Lecture Notes till week 8. ISYE6501timeline Fall. On Studocu you find all the lecture notes, summaries and study guides you need to pass your exams with better grades.Developed by Microsoft and included in its Office suite of productivity software, Word allows you to create print-formatted documents such as letters, envelopes, brochures and form...ISYE 6501. Subject. Computer Science. Date. Jul 17, 2023. Pages. 38. Uploaded by AgentSeahorseMaster1773 on coursehero.com. Helpful. Unhelpful. Home / …Introduction to Analytics Modeling - Georgia Tech OMDS - olivierzach/GTx_6501. Skip to content. Navigation Menu Toggle navigation. Sign in Product Actions. Automate any …Midterm 1: 84/100; Midterm 2: 87/100; Final Exam: 93/100; Final Course Project: 100/100; Although I can’t claim I aced them all, I certainly had an improving trajectory. And now that is out...ISYE 6501, Introduction to Analytics Modeling Midterm #2 – Wednesday, November 9, 2022 75 minute time limit INSTRUCTIONS. Work alone. Do not collaborate with or copy from …

ISYE 6501 Midterm 2 Part 1 Latest 2023 Rated A greedy algorithm at each step, the algorithm does the thing that looks best without taking future options into consideration; more classical variable selection methods stepwise - (forward, backward, combination) lasso elastic net available metrics fo.... Angelika cinema showtimes

isye 6501 midterm 2

ISYE 6501 - Midterm 2. Term. 1 / 159. when might overfitting occur. Click the card to flip 👆. Definition. 1 / 159. when the # of factors is close to or larger than the # of data points causing the model to potentially fit too closely to random effects. Click the card to flip 👆. Prof Jokol will provide the curves for each midterms. r/OMSA users are usually people who score better. Iirc the ta's will post the grade distribution in more detail than the standard mean/max/min values that canvas provides. They additionally provide pseudo guidance on how the test would be curved it it was curved.2. Exam (elaborations) - Isye 6501 - midterm 1 preparation (mod 1-10) questions and correct answers 3. Exam (elaborations) - Nurs 6501 final exam questions ...ISYE 6501 curve . ISYE6501 iAM ... Midterm 2 was the one I scored the worst on, but honestly it was the final that I felt the most stress, especially the last few scenario based questions where it is not clear at all what the right approach may be. ... Because a lot of people (including, hello, me) take 6501 MM for the advanced standing credit ...20 of 20. Quiz yourself with questions and answers for ISYE 6501 - Midterm 2, so you can be ready for test day. Explore quizzes and practice tests created by teachers and students or create one from your course material.6501 - Midterm 2 Learn with flashcards, games, and more — for free. ISYE 6501 Midterm 2 _ Intro Analytics Modeling - ISYE-6501-OAN_O01_QCH_A. ISYE 6501 Midterm Exam 1 Version 2 (2022/2023) A+ Graded. ISYE 6501 MIDTERM QUIZ 1 WITH CORRECT ANSWERS UPDATED 2022 The seven best market sectors for the fourth quarter are home to top-performing stocks and ideas that will benefit even in a slowing economy. Look at these sectors to navigate the ...ISYE 6501 Midterm 2 Intro Analytics Modeling ISYE 6501 O01 OAN O01 MSA. ISYE_6501_Midterm_2___Intro_Analytics_Modeling___ISYE_6501_O01_OAN_O01... View more. Course. nursing (nur 601) 760Documents. Students shared 760 documents in this course. University. Chamberlain University. Academic year:2022/2023. Uploaded by: Amos Ndungu.ISYE 6501 - Midterm 2. 160 terms. oanise. ISYE 6501 - Final Exam. 414 terms. oanise. Other sets by this creator. Supply Chain - MGMT 8803. 6 terms. Nicholas_Taylor614. MGT 8803 Final - 165 cards cl. 165 terms. Nicholas_Taylor614. MGT8803 - Supply Chain. 31 terms. Nicholas_Taylor614. CSE 6040 - Midterm 1. 45 terms.Institution. ISYE 6501. ISYE 6501 Midterm 2 Questions with All Correct Answers Rows - ANSWER Data points are values in data tables Columns - ANSWER The 'answer' for each data point (response/outcome) Structured Data - ANSWER Quantitative, Categorical, Binary, Unrelated, Time Series Unstructu... [Show more]ISYE 6501 Midterm 2 Intro Analytics Modeling - ISYE-6501-OAN O01 QCH ASY. Intro to Analytics Modeling 100% (5) 45. ISYE 6501 Midterm 2 - practice material. Intro to Analytics Modeling 100% (3) 12. ISYE6501 Homework 4 - eee. Intro to Analytics Modeling 100% (2) 67. Quiz History- ISy E 6501 Final Quiz copy.Nov 27, 2021 · Class notes. $8.99. Also available in package deal from $15.49. Add to cart Add to wishlist. 100% satisfaction guarantee. Immediately available after payment. Both online and in PDF. No strings attached. Jul 13, 2021 · ISYE 6501 Midterm 2 Due Jul 12 at 9am Points 100.02 Questions 48 Available after Jul 1 at 9am Time Limit 90 Minutes Instructions Honorlock Chrome Extension This exam requires Google Chrome and the Honorlock Chrome Extension. .

Popular Topics